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/* SPDX-License-Identifier: GPL-2.0 */
/* esp_scsi.h: Defines and structures for the ESP driver.
* Copyright (C) 2007 David S. Miller (
#ifndef _ESP_SCSI_H
#define _ESP_SCSI_H
/* Access Description Offset */
#define ESP_TCLOW 0x00UL /* rw Low bits transfer count 0x00 */
#define ESP_TCMED 0x01UL /* rw Mid bits transfer count 0x04 */
#define ESP_FDATA 0x02UL /* rw FIFO data bits 0x08 */
#define ESP_CMD 0x03UL /* rw SCSI command bits 0x0c */
#define ESP_STATUS 0x04UL /* ro ESP status register 0x10 */
#define ESP_BUSID ESP_STATUS /* wo BusID for sel/resel 0x10 */
#define ESP_INTRPT 0x05UL /* ro Kind of interrupt 0x14 */
#define ESP_TIMEO ESP_INTRPT /* wo Timeout for sel/resel 0x14 */
#define ESP_SSTEP 0x06UL /* ro Sequence step register 0x18 */
#define ESP_STP ESP_SSTEP /* wo Transfer period/sync 0x18 */
#define ESP_FFLAGS 0x07UL /* ro Bits current FIFO info 0x1c */
#define ESP_SOFF ESP_FFLAGS /* wo Sync offset 0x1c */
#define ESP_CFG1 0x08UL /* rw First cfg register 0x20 */
#define ESP_CFACT 0x09UL /* wo Clock conv factor 0x24 */
#define ESP_STATUS2 ESP_CFACT /* ro HME status2 register 0x24 */
#define ESP_CTEST 0x0aUL /* wo Chip test register 0x28 */
#define ESP_CFG2 0x0bUL /* rw Second cfg register 0x2c */
#define ESP_CFG3 0x0cUL /* rw Third cfg register 0x30 */
#define ESP_CFG4 0x0dUL /* rw Fourth cfg register 0x34 */
#define ESP_TCHI 0x0eUL /* rw High bits transf count 0x38 */
#define ESP_UID ESP_TCHI /* ro Unique ID code 0x38 */
#define FAS_RLO ESP_TCHI /* rw HME extended counter 0x38 */
#define ESP_FGRND 0x0fUL /* rw Data base for fifo 0x3c */
#define FAS_RHI ESP_FGRND /* rw HME extended counter 0x3c */
#define SBUS_ESP_REG_SIZE 0x40UL
/* Bitfield meanings for the above registers. */
/* ESP config reg 1, read-write, found on all ESP chips */
#define ESP_CONFIG1_ID 0x07 /* My BUS ID bits */
#define ESP_CONFIG1_CHTEST 0x08 /* Enable ESP chip tests */
#define ESP_CONFIG1_PENABLE 0x10 /* Enable parity checks */
#define ESP_CONFIG1_PARTEST 0x20 /* Parity test mode enabled? */
#define ESP_CONFIG1_SRRDISAB 0x40 /* Disable SCSI reset reports */
#define ESP_CONFIG1_SLCABLE 0x80 /* Enable slow cable mode */
/* ESP config reg 2, read-write, found only on esp100a+esp200+esp236 chips */
#define ESP_CONFIG2_DMAPARITY 0x01 /* enable DMA Parity (200,236) */
#define ESP_CONFIG2_REGPARITY 0x02 /* enable reg Parity (200,236) */
#define ESP_CONFIG2_BADPARITY 0x04 /* Bad parity target abort */
#define ESP_CONFIG2_SCSI2ENAB 0x08 /* Enable SCSI-2 features (tgtmode) */
#define ESP_CONFIG2_HI 0x10 /* High Impedance DREQ ??? */
#define ESP_CONFIG2_HMEFENAB 0x10 /* HME features enable */
#define ESP_CONFIG2_BCM 0x20 /* Enable byte-ctrl (236) */
#define ESP_CONFIG2_DISPINT 0x20 /* Disable pause irq (hme) */
#define ESP_CONFIG2_FENAB 0x40 /* Enable features (fas100,216) */
#define ESP_CONFIG2_SPL 0x40 /* Enable status-phase latch (236) */
#define ESP_CONFIG2_MKDONE 0x40 /* HME magic feature */
#define ESP_CONFIG2_HME32 0x80 /* HME 32 extended */
#define ESP_CONFIG2_MAGIC 0xe0 /* Invalid bits... */
/* ESP config register 3 read-write, found only esp236+fas236+fas100a+hme chips */
#define ESP_CONFIG3_FCLOCK 0x01 /* FAST SCSI clock rate (esp100a/hme) */
#define ESP_CONFIG3_TEM 0x01 /* Enable thresh-8 mode (esp/fas236) */
#define ESP_CONFIG3_FAST 0x02 /* Enable FAST SCSI (esp100a/hme) */
#define ESP_CONFIG3_ADMA 0x02 /* Enable alternate-dma (esp/fas236) */
#define ESP_CONFIG3_TENB 0x04 /* group2 SCSI2 support (esp100a/hme) */
#define ESP_CONFIG3_SRB 0x04 /* Save residual byte (esp/fas236) */
#define ESP_CONFIG3_TMS 0x08 /* Three-byte msg's ok (esp100a/hme) */
#define ESP_CONFIG3_FCLK 0x08 /* Fast SCSI clock rate (esp/fas236) */
#define ESP_CONFIG3_IDMSG 0x10 /* ID message checking (esp100a/hme) */
#define ESP_CONFIG3_FSCSI 0x10 /* Enable FAST SCSI (esp/fas236) */
#define ESP_CONFIG3_GTM 0x20 /* group2 SCSI2 support (esp/fas236) */
#define ESP_CONFIG3_IDBIT3 0x20 /* Bit 3 of HME SCSI-ID (hme) */
#define ESP_CONFIG3_TBMS 0x40 /* Three-byte msg's ok (esp/fas236) */
#define ESP_CONFIG3_EWIDE 0x40 /* Enable Wide-SCSI (hme) */
#define ESP_CONFIG3_IMS 0x80 /* ID msg chk'ng (esp/fas236) */
#define ESP_CONFIG3_OBPUSH 0x80 /* Push odd-byte to dma (hme) */
/* ESP config register 4 read-write */
#define ESP_CONFIG4_BBTE 0x01 /* Back-to-back transfers (fsc) */
#define ESP_CONGIG4_TEST 0x02 /* Transfer counter test mode (fsc) */
#define ESP_CONFIG4_RADE 0x04 /* Active negation (am53c974/fsc) */
#define ESP_CONFIG4_RAE 0x08 /* Act. negation REQ/ACK (am53c974) */
#define ESP_CONFIG4_PWD 0x20 /* Reduced power feature (am53c974) */
#define ESP_CONFIG4_GE0 0x40 /* Glitch eater bit 0 (am53c974) */
#define ESP_CONFIG4_GE1 0x80 /* Glitch eater bit 1 (am53c974) */
#define ESP_CONFIG_GE_12NS (0)
/* ESP command register read-write */
/* Group 1 commands: These may be sent at any point in time to the ESP
* chip. None of them can generate interrupts 'cept
* the "SCSI bus reset" command if you have not disabled
* SCSI reset interrupts in the config1 ESP register.
#define ESP_CMD_NULL 0x00 /* Null command, ie. a nop */
#define ESP_CMD_FLUSH 0x01 /* FIFO Flush */
#define ESP_CMD_RC 0x02 /* Chip reset */
#define ESP_CMD_RS 0x03 /* SCSI bus reset */
/* Group 2 commands: ESP must be an initiator and connected to a target
* for these commands to work.
#define ESP_CMD_TI 0x10 /* Transfer Information */
#define ESP_CMD_ICCSEQ 0x11 /* Initiator cmd complete sequence */
#define ESP_CMD_MOK 0x12 /* Message okie-dokie */
#define ESP_CMD_TPAD 0x18 /* Transfer Pad */
#define ESP_CMD_SATN 0x1a /* Set ATN */
#define ESP_CMD_RATN 0x1b /* De-assert ATN */
/* Group 3 commands: ESP must be in the MSGOUT or MSGIN state and be connected
* to a target as the initiator for these commands to work.
#define ESP_CMD_SMSG 0x20 /* Send message */
#define ESP_CMD_SSTAT 0x21 /* Send status */
#define ESP_CMD_SDATA 0x22 /* Send data */
#define ESP_CMD_DSEQ 0x23 /* Discontinue Sequence */
#define ESP_CMD_TSEQ 0x24 /* Terminate Sequence */
#define ESP_CMD_TCCSEQ 0x25 /* Target cmd cmplt sequence */
#define ESP_CMD_DCNCT 0x27 /* Disconnect */
#define ESP_CMD_RMSG 0x28 /* Receive Message */
#define ESP_CMD_RCMD 0x29 /* Receive Command */
#define ESP_CMD_RDATA 0x2a /* Receive Data */
#define ESP_CMD_RCSEQ 0x2b /* Receive cmd sequence */
/* Group 4 commands: The ESP must be in the disconnected state and must
* not be connected to any targets as initiator for
* these commands to work.
#define ESP_CMD_RSEL 0x40 /* Reselect */
#define ESP_CMD_SEL 0x41 /* Select w/o ATN */
#define ESP_CMD_SELA 0x42 /* Select w/ATN */
#define ESP_CMD_SELAS 0x43 /* Select w/ATN & STOP */
#define ESP_CMD_ESEL 0x44 /* Enable selection */
#define ESP_CMD_DSEL 0x45 /* Disable selections */
#define ESP_CMD_SA3 0x46 /* Select w/ATN3 */
#define ESP_CMD_RSEL3 0x47 /* Reselect3 */
/* This bit enables the ESP's DMA on the SBus */
#define ESP_CMD_DMA 0x80 /* Do DMA? */
/* ESP status register read-only */
#define ESP_STAT_PIO 0x01 /* IO phase bit */
#define ESP_STAT_PCD 0x02 /* CD phase bit */
#define ESP_STAT_PMSG 0x04 /* MSG phase bit */
#define ESP_STAT_PMASK 0x07 /* Mask of phase bits */
#define ESP_STAT_TDONE 0x08 /* Transfer Completed */
#define ESP_STAT_TCNT 0x10 /* Transfer Counter Is Zero */
#define ESP_STAT_PERR 0x20 /* Parity error */
#define ESP_STAT_SPAM 0x40 /* Real bad error */
/* This indicates the 'interrupt pending' condition on esp236, it is a reserved
* bit on other revs of the ESP.
#define ESP_STAT_INTR 0x80 /* Interrupt */
/* The status register can be masked with ESP_STAT_PMASK and compared
* with the following values to determine the current phase the ESP
* (at least thinks it) is in. For our purposes we also add our own
* software 'done' bit for our phase management engine.
#define ESP_DOP (0) /* Data Out */
#define ESP_DIP (ESP_STAT_PIO) /* Data In */
#define ESP_CMDP (ESP_STAT_PCD) /* Command */
#define ESP_STATP (ESP_STAT_PCD|ESP_STAT_PIO) /* Status */
#define ESP_MOP (ESP_STAT_PMSG|ESP_STAT_PCD) /* Message Out */
/* HME only: status 2 register */
#define ESP_STAT2_SCHBIT 0x01 /* Upper bits 3-7 of sstep enabled */
#define ESP_STAT2_FFLAGS 0x02 /* The fifo flags are now latched */
#define ESP_STAT2_XCNT 0x04 /* The transfer counter is latched */
#define ESP_STAT2_CREGA 0x08 /* The command reg is active now */
#define ESP_STAT2_WIDE 0x10 /* Interface on this adapter is wide */
#define ESP_STAT2_F1BYTE 0x20 /* There is one byte at top of fifo */
#define ESP_STAT2_FMSB 0x40 /* Next byte in fifo is most significant */
#define ESP_STAT2_FEMPTY 0x80 /* FIFO is empty */
/* ESP interrupt register read-only */
#define ESP_INTR_S 0x01 /* Select w/o ATN */
#define ESP_INTR_SATN 0x02 /* Select w/ATN */
#define ESP_INTR_RSEL 0x04 /* Reselected */
#define ESP_INTR_FDONE 0x08 /* Function done */
#define ESP_INTR_BSERV 0x10 /* Bus service */
#define ESP_INTR_DC 0x20 /* Disconnect */
#define ESP_INTR_IC 0x40 /* Illegal command given */
#define ESP_INTR_SR 0x80 /* SCSI bus reset detected */
/* ESP sequence step register read-only */
#define ESP_STEP_VBITS 0x07 /* Valid bits */
#define ESP_STEP_ASEL 0x00 /* Selection&Arbitrate cmplt */
#define ESP_STEP_SID 0x01 /* One msg byte sent */
#define ESP_STEP_NCMD 0x02 /* Was not in command phase */
#define ESP_STEP_PPC 0x03 /* Early phase chg caused cmnd
* bytes to be lost
#define ESP_STEP_FINI4 0x04 /* Command was sent ok */
/* Ho hum, some ESP's set the step register to this as well... */
#define ESP_STEP_FINI5 0x05
#define ESP_STEP_FINI6 0x06
#define ESP_STEP_FINI7 0x07
/* ESP chip-test register read-write */
#define ESP_TEST_TARG 0x01 /* Target test mode */
#define ESP_TEST_INI 0x02 /* Initiator test mode */
#define ESP_TEST_TS 0x04 /* Tristate test mode */
/* ESP unique ID register read-only, found on fas236+fas100a only */
#define ESP_UID_FAM 0xf8 /* ESP family bitmask */
#define ESP_FAMILY(uid) (((uid) & ESP_UID_FAM) >> 3)
/* Values for the ESP family bits */
#define ESP_UID_F100A 0x00 /* ESP FAS100A */
#define ESP_UID_F236 0x02 /* ESP FAS236 */
#define ESP_UID_HME 0x0a /* FAS HME */
#define ESP_UID_FSC 0x14 /* NCR/Symbios Logic 53CF9x-2 */
/* ESP fifo flags register read-only */
/* Note that the following implies a 16 byte FIFO on the ESP. */
#define ESP_FF_FBYTES 0x1f /* Num bytes in FIFO */
#define ESP_FF_ONOTZERO 0x20 /* offset ctr not zero (esp100) */
#define ESP_FF_SSTEP 0xe0 /* Sequence step */
/* ESP clock conversion factor register write-only */
#define ESP_CCF_F0 0x00 /* 35.01MHz - 40MHz */
#define ESP_CCF_NEVER 0x01 /* Set it to this and die */
#define ESP_CCF_F2 0x02 /* 10MHz */
#define ESP_CCF_F3 0x03 /* 10.01MHz - 15MHz */
#define ESP_CCF_F4 0x04 /* 15.01MHz - 20MHz */
#define ESP_CCF_F5 0x05 /* 20.01MHz - 25MHz */
#define ESP_CCF_F6 0x06 /* 25.01MHz - 30MHz */
#define ESP_CCF_F7 0x07 /* 30.01MHz - 35MHz */
/* HME only... */
#define ESP_BUSID_RESELID 0x10
#define ESP_BUSID_CTR32BIT 0x40
#define ESP_BUS_TIMEOUT 250 /* In milli-seconds */
#define ESP_TIMEO_CONST 8192
#define ESP_NEG_DEFP(mhz, cfact) \
((ESP_BUS_TIMEOUT * ((mhz) / 1000)) / (8192 * (cfact)))
#define ESP_HZ_TO_CYCLE(hertz) ((1000000000) / ((hertz) / 1000))
#define ESP_TICK(ccf, cycle) ((7682 * (ccf) * (cycle) / 1000))
/* For slow to medium speed input clock rates we shoot for 5mb/s, but for high
* input clock rates we try to do 10mb/s although I don't think a transfer can
* even run that fast with an ESP even with DMA2 scatter gather pipelining.
#define SYNC_DEFP_SLOW 0x32 /* 5mb/s */
#define SYNC_DEFP_FAST 0x19 /* 10mb/s */
struct esp_cmd_priv {
int num_sg;
int cur_residue;
struct scatterlist *prv_sg;
struct scatterlist *cur_sg;
int tot_residue;
#define ESP_CMD_PRIV(CMD) ((struct esp_cmd_priv *)(&(CMD)->SCp))
/* NOTE: this enum is ordered based on chip features! */
enum esp_rev {
ESP100, /* NCR53C90 - very broken */
ESP100A, /* NCR53C90A */
PCSCSI, /* AM53c974 */
FSC, /* NCR/Symbios Logic 53CF9x-2 */
struct esp_cmd_entry {
struct list_head list;
struct scsi_cmnd *cmd;
unsigned int saved_cur_residue;
struct scatterlist *saved_prv_sg;
struct scatterlist *saved_cur_sg;
unsigned int saved_tot_residue;
u8 flags;
#define ESP_CMD_FLAG_WRITE 0x01 /* DMA is a write */
#define ESP_CMD_FLAG_AUTOSENSE 0x04 /* Doing automatic REQUEST_SENSE */
#define ESP_CMD_FLAG_RESIDUAL 0x08 /* AM53c974 BLAST residual */
u8 tag[2];
u8 orig_tag[2];
u8 status;
u8 message;
unsigned char *sense_ptr;
unsigned char *saved_sense_ptr;
dma_addr_t sense_dma;
struct completion *eh_done;
#define ESP_MAX_TARGET 16
#define ESP_MAX_LUN 8
#define ESP_MAX_TAG 256
struct esp_lun_data {
struct esp_cmd_entry *non_tagged_cmd;
int num_tagged;
int hold;
struct esp_cmd_entry *tagged_cmds[ESP_MAX_TAG];
struct esp_target_data {
/* These are the ESP_STP, ESP_SOFF, and ESP_CFG3 register values which
* match the currently negotiated settings for this target. The SCSI
* protocol values are maintained in spi_{offset,period,wide}(starget).
u8 esp_period;
u8 esp_offset;
u8 esp_config3;
u8 flags;
#define ESP_TGT_WIDE 0x01
#define ESP_TGT_NEGO_WIDE 0x04
#define ESP_TGT_NEGO_SYNC 0x08
#define ESP_TGT_CHECK_NEGO 0x40
#define ESP_TGT_BROKEN 0x80
/* When ESP_TGT_CHECK_NEGO is set, on the next scsi command to this
* device we will try to negotiate the following parameters.
u8 nego_goal_period;
u8 nego_goal_offset;
u8 nego_goal_width;
u8 nego_goal_tags;
struct scsi_target *starget;
struct esp_event_ent {
u8 type;
#define ESP_EVENT_TYPE_CMD 0x02
u8 val;
u8 sreg;
u8 seqreg;
u8 sreg2;
u8 ireg;
u8 select_state;
u8 event;
u8 __pad;
struct esp;
struct esp_driver_ops {
/* Read and write the ESP 8-bit registers. On some
* applications of the ESP chip the registers are at 4-byte
* instead of 1-byte intervals.
void (*esp_write8)(struct esp *esp, u8 val, unsigned long reg);
u8 (*esp_read8)(struct esp *esp, unsigned long reg);
/* Return non-zero if there is an IRQ pending. Usually this
* status bit lives in the DMA controller sitting in front of
* the ESP. This has to be accurate or else the ESP interrupt
* handler will not run.
int (*irq_pending)(struct esp *esp);
/* Return the maximum allowable size of a DMA transfer for a
* given buffer.
u32 (*dma_length_limit)(struct esp *esp, u32 dma_addr,
u32 dma_len);
/* Reset the DMA engine entirely. On return, ESP interrupts
* should be enabled. Often the interrupt enabling is
* controlled in the DMA engine.
void (*reset_dma)(struct esp *esp);
/* Drain any pending DMA in the DMA engine after a transfer.
* This is for writes to memory.
void (*dma_drain)(struct esp *esp);
/* Invalidate the DMA engine after a DMA transfer. */
void (*dma_invalidate)(struct esp *esp);
/* Setup an ESP command that will use a DMA transfer.
* The 'esp_count' specifies what transfer length should be
* programmed into the ESP transfer counter registers, whereas
* the 'dma_count' is the length that should be programmed into
* the DMA controller. Usually they are the same. If 'write'
* is non-zero, this transfer is a write into memory. 'cmd'
* holds the ESP command that should be issued by calling
* scsi_esp_cmd() at the appropriate time while programming
* the DMA hardware.
void (*send_dma_cmd)(struct esp *esp, u32 dma_addr, u32 esp_count,
u32 dma_count, int write, u8 cmd);
/* Return non-zero if the DMA engine is reporting an error
* currently.
int (*dma_error)(struct esp *esp);
#define ESP_MAX_MSG_SZ 8
#define ESP_EVENT_LOG_SZ 32
struct esp {
void __iomem *regs;
void __iomem *dma_regs;
const struct esp_driver_ops *ops;
struct Scsi_Host *host;
struct device *dev;
struct esp_cmd_entry *active_cmd;
struct list_head queued_cmds;
struct list_head active_cmds;
u8 *command_block;
dma_addr_t command_block_dma;
unsigned int data_dma_len;
/* The following are used to determine the cause of an IRQ. Upon every
* IRQ entry we synchronize these with the hardware registers.
u8 sreg;
u8 seqreg;
u8 sreg2;
u8 ireg;
u32 prev_hme_dmacsr;
u8 prev_soff;
u8 prev_stp;
u8 prev_cfg3;
u8 num_tags;
struct list_head esp_cmd_pool;
struct esp_target_data target[ESP_MAX_TARGET];
int fifo_cnt;
u8 fifo[16];
struct esp_event_ent esp_event_log[ESP_EVENT_LOG_SZ];
int esp_event_cur;
u8 msg_out[ESP_MAX_MSG_SZ];
int msg_out_len;
u8 msg_in[ESP_MAX_MSG_SZ];
int msg_in_len;
u8 bursts;
u8 config1;
u8 config2;
u8 config4;
u8 scsi_id;
u32 scsi_id_mask;
enum esp_rev rev;
u32 flags;
#define ESP_FLAG_DIFFERENTIAL 0x00000001
#define ESP_FLAG_RESETTING 0x00000002
#define ESP_FLAG_WIDE_CAPABLE 0x00000008
#define ESP_FLAG_QUICKIRQ_CHECK 0x00000010
#define ESP_FLAG_DISABLE_SYNC 0x00000020
#define ESP_FLAG_USE_FIFO 0x00000040
#define ESP_FLAG_NO_DMA_MAP 0x00000080
u8 select_state;
#define ESP_SELECT_NONE 0x00 /* Not selecting */
#define ESP_SELECT_BASIC 0x01 /* Select w/o MSGOUT phase */
#define ESP_SELECT_MSGOUT 0x02 /* Select with MSGOUT */
/* When we are not selecting, we are expecting an event. */
u8 event;
#define ESP_EVENT_NONE 0x00
#define ESP_EVENT_CMD_START 0x01
#define ESP_EVENT_CMD_DONE 0x02
#define ESP_EVENT_DATA_IN 0x03
#define ESP_EVENT_DATA_OUT 0x04
#define ESP_EVENT_DATA_DONE 0x05
#define ESP_EVENT_MSGIN 0x06
#define ESP_EVENT_MSGOUT 0x09
#define ESP_EVENT_STATUS 0x0b
#define ESP_EVENT_FREE_BUS 0x0c
#define ESP_EVENT_RESET 0x10
/* Probed in esp_get_clock_params() */
u32 cfact;
u32 cfreq;
u32 ccycle;
u32 ctick;
u32 neg_defp;
u32 sync_defp;
/* Computed in esp_reset_esp() */
u32 max_period;
u32 min_period;
u32 radelay;
/* ESP_CMD_SELAS command state */
u8 *cmd_bytes_ptr;
int cmd_bytes_left;
struct completion *eh_reset;
void *dma;
int dmarev;
/* These are used by esp_send_pio_cmd() */
u8 __iomem *fifo_reg;
int send_cmd_error;
u32 send_cmd_residual;
/* A front-end driver for the ESP chip should do the following in
* it's device probe routine:
* 1) Allocate the host and private area using scsi_host_alloc()
* with size 'sizeof(struct esp)'. The first argument to
* scsi_host_alloc() should be &scsi_esp_template.
* 2) Set host->max_id as appropriate.
* 3) Set esp->host to the scsi_host itself, and esp->dev
* to the device object pointer.
* 4) Hook up esp->ops to the front-end implementation.
* 5) If the ESP chip supports wide transfers, set ESP_FLAG_WIDE_CAPABLE
* in esp->flags.
* 6) Map the DMA and ESP chip registers.
* 7) DMA map the ESP command block, store the DMA address
* in esp->command_block_dma.
* 8) Register the scsi_esp_intr() interrupt handler.
* 9) Probe for and provide the following chip properties:
* esp->scsi_id (assign to esp->host->this_id too)
* esp->scsi_id_mask
* If ESP bus is differential, set ESP_FLAG_DIFFERENTIAL
* esp->cfreq
* DMA burst bit mask in esp->bursts, if necessary
* 10) Perform any actions necessary before the ESP device can
* be programmed for the first time. On some configs, for
* example, the DMA engine has to be reset before ESP can
* be programmed.
* 11) If necessary, call dev_set_drvdata() as needed.
* 12) Call scsi_esp_register() with prepared 'esp' structure.
* 13) Check scsi_esp_register() return value, release all resources
* if an error was returned.
extern struct scsi_host_template scsi_esp_template;
extern int scsi_esp_register(struct esp *);
extern void scsi_esp_unregister(struct esp *);
extern irqreturn_t scsi_esp_intr(int, void *);
extern void scsi_esp_cmd(struct esp *, u8);
extern void esp_send_pio_cmd(struct esp *esp, u32 dma_addr, u32 esp_count,
u32 dma_count, int write, u8 cmd);
#endif /* !(_ESP_SCSI_H) */